Electrolytic condenser



Feb. 20,v 1910.

P. McK. DEI-:LEY

ELECTROLYTIC CONDENSER Filed May 22, 1936 lll/lill VII/111111 INVENTOR.Paul 772c- Wag/WM@ ATTORNEY.

Patented Feb. 20, 1940 UNITED STATES 4PATENT OFFICE ELEC'IROLYTICCONDENSER Y Application May 22, 1936, Serial N0. 81,252

12 Claims.

The present invention relates to electrical condensers, morespecifically to condensers of the electrolytic type, and to an efficientand reliable mechanical and electrical construction of such 5condensers.

In the construction of wet electrolytic condensers, reliable vents aredesirable in connection with the liquid electrolyte where a suitablemeans is necessary for relieving the pressure of the in- 10 terior ofthe container or casing caused by gases or vapors developed during theoperation by the electric current passing through the condenser andlikely to cause impairment of the function or complete destruction ofthe devices.

n my copendingv application, Serial No. 53,367, filed December 7, 1935,l have described a vent comprising a flexible diaphragm such as a rubberdiaphragm spanning an opening in the container accommodating theelectrolyte and the condenser elements and covered by an outwardlyarched or vaulted cap. When excess gas pressure is developed within thecontainer, the rubber diaphragm which has a thin mid portion providedwith a normally closed puncture of pin-hole size is distended outwardlyunderneath the 'vaulted cover in such a manner that with a certainpressure the puncture is opened and the gas allowed ytc escape to theoutside.

One of the features of the present invention relates to an improvedconstruction of this general character allowing of a more accurateadjustment of the pressure at which the gases are released from thecontainer and capable of operating at a substantially lower pressure andwith increased liability as' compared with known constructions such asdescribed in my copending application Vabove referred to.

Another feature is the method of holding the insulated terminal and theanode through an airtight, water-tight, mechanically strong and flexiblearrangement which enables a very eiiicient construction acting both as amechanical and electrically insulated structure.

Other important features are evident from the specification and drawingand will become more apparent from the following detailed` descriptiontaken with reference to the accompanying draw-l ing, in which Fig. 1 isan elevational cross-sectional view of an electrolytic condenserprovided with a vent structure according to the invention.

Fig. 2 is a top view of the condenser according to Fig. l. Y

Fig. 3 is a cross-sectional `view taken on lin 3-3 of Fig. 1. Y

Fig. 4 is an enlarged isometric detail View showing the rubber gasketand vent diaphragm in section.

Figs. 5 and 6 are enlarged partial cross-section views of a condenser ofthe type according to Fig. 1 illustrating modifications oi the ventstructure according to the invention.

Like reference numerals identify like parts in the different `views ofthe drawing.

The condenser illustrated comprises a metallic container l ofcylindrical shape consisting of a suitable material such as aluminum,copper, or. commercial alloy, and accommodating a suitable electrolytesolution. The cylinder or container may be plated both inside andoutside with chromium, nickel, copper, cadmium or ani7 other suitablematerial, and it may be etched inside and outside if required. Thecontainer has a bottom wall l I and a top wall i3, the latter havingassociated therewith a combined gasket and vent diaphragm consisting ofrubber or other equivalent iiexible material. The bottom wall isprovided with a hollow screw threaded depending neck 2 serving formounting the condenser on a support plate 3 in an inverted position inaccordance with standard practice, or the container :may be of thestandard type with the depending neck but without screw threading. Theanode or filmed electrode shown at 4 is supported by a rod of iilmforming material, such as aluminum, which in the example illustratedconsists of a sheet or strip of film forming material preferably highpurity aluminum of relatively small thickness folded back and forth inaccordion fashion and riveted or otherwise secured to the rod 5. Forthis purpose the shown swaged or flattened throughout its ser lengthadjoining the electrode d and pi ded with dish-shaped depressions toenable a simple and eicient connection with the central pleat of theanode 4 by means of rivets 6 or by a Welding, or any other suitableconnection. The pleats of the anode 4 may be of equal width or ofgradually decreasing width towards the container wall similar asdescribed in my copending application, or the anode may bewoundconcentrically with the riser rod 5 connected tojthe inside end ofthe anode, or the riser rod maybe bent in such a manner as to beconnected to the outside turn of the anode. Further details with regardto the material of rod 5, rivet 6, etc., may be substantially the sameas described in said copending application. Alternatively, the anode maybe cast or extruded with or without the'riser rod being an integral partof the casting. lili par - such as rubber placed inside the neck 2 ofthe container. rIhe lower' part of the neck 2 is pressed or spuninwardly against the rod 5to compress the rubber plug ll into asemi-cone shape with gradually decreasing pressure on the insulatingmaterial as the base ol the cone is reached, uniformly in all,directions to secure a liquid tight seal between the neck 2, plug l androd 5. The

lower end of the rod projecting through the v'plug 'I constitutes theterminal of the anode and is provided with a suitable connectingmeans,such as clamping screw or soldering lug B having an integral sleeveforced over the rod 5 or otherwise connected thereto to secure closemechanical and electrical contact.

In order to prevent the anode 4 from coming in accidental Contact withthe wall of the container, a cylindrical spacer 9 of suitable material,such as hard rubber, Celluloid, gauze or the like is placed between theanode and the inner wall of the container. In order to allow free accessof the electrolyte to both the container serving as the'cathode and tothe anode, the spacer 9 is provided with perforations ill of suitablesize and appropriate number.

The top of the container is hermetically closed by a pair of disc shapedcover members or caps I3 and I6, the latter consisting of iexiblematerial, such as rubber, and serving as a combined sealing gasket andvent diaphragm, while the former preferably consists of metal and servesas a protection for the vent. In order to obtain a liquid-tight seal,the upper edge of the container is shown to be bent at first inwardlyand then in an outward direction transversely to the axis of thecontainer so as to provide a rim or flange shown at I5. Both the coverI3 and the rubber gasket I4 are provided with depressed mid-porn Y tionsI6 and I1 snugly fitting one within each otherand the container at I3.

.The outer edges or shoulders of the ventgasket I4 and the cover I3 arethen rolled or spun over the flange I 5 of the container as shown toeect a liquid tight seal between the container and cover I3. The centerportion or cupshaped depression Il of the rubber gasket has a I thinnermid-section than the remaining 'parts as shown more clearly at I9 inFigure a.v This section is provided with a' central incision or puncture22 of pin hole size closed under normal conditions and preventingleakage ,and exposure of the electrolyte in the container to the outsideatmosphere. In order to enable the diaphragm Il to distend under theinfluence of' excess pressure developed in the container, I have shownin the example illustrated 'the mid-portion I6 of the cap or cover I3 ofconvex or outwardly arched shape to allow the diaphragm to curve upunder the influence of the gas pressure in the container until thepuncture 22 opens and the excess gas is allowed to escape tothefaoutsidethrough an escape hole or aperture 20 in the center of cap I5,

The vent diaphragm according to the present' invention is of-specialconstruction enabling a very close and accurate adjustment of the gasvpressure at whichthe puncture 22 is to open and relieve the interior ofthe condenser from excess gases. For thispurpose, I have shown anannular rim 2I in the example illustrated integral with the diaphragm orotherwise connected theretoin any suitable manner and 'surrounding thethin punctured 'center section of the diaphragm.v Alternatively, the rim2l may beconectedto the ous figures.

cap I3 as shown in Figures 5 and v6. In a construction of this type itis seen that if the gas pressure is gradually increased, at first theentire diaphragm will distend or curve up until shortly before thecritical pressure is reached, the rim 2l strikes the cover I6 preventingfurther distention of the outer diaphragm portion. It the pressureincreases further, substantially only the thin center section I9 will bedistended at a much greater rate due to its smaller thickness comparedwith the main section I'l. rI'hus the puncture in the center section I8will be opened by a slight pressure increase and release the excessgases. By properly designing the height of the'annular rim 2| and itsnormal spacing from the cover I6, the critical operating pressure of thevent may be closely and accurately predetermined and adjusted for valuessubstantially closer to the normal operating pressure as` compared withvent constructions of the type heretoore known.

Thus it was found by experiment that with a vent of the typeillustrated, release ofexcess gas could be obtained at a pressure offive pounds per square inch as compared with a minimum pressure offifteen pounds per square inch required when using a vent constructionof heretofore known type. In Figures 5 and 6, I have shown modifiedconstructions of ka vent ofthe general character described. In thearrangement according to Figure 5, the intervening annular spacer 28 isshown integral with a substantially iiat cover 21 pro- Vided with acentral aperture or escape hole 29 similar as described before. Therubber diaphragm has an outer part or rim 25 and an inner depressed part26 similar-as shown in the previ- The inner or vent portion proper isshown to be of gradually varying thickness increasing from the center tothe outside vto secure the advantage and novel eiiects of an increasingdegree of distension towards the center by the gas pressure analogous tothe construction y described by the previous gures.

Figure 6 also shows an annular spacer 33 being integralwith the centervportion of the cover or cap 32 or connected thereto in any otherconvenient manner. Item 34 represents a central escape hole similar asin thei'fprevious lgures. vThe rubber diaphragm has an outer or gasketportion 30 and differs from the previous construction in that itscentral section 31 of less thickness is ush with the upper face of thediaphragm as compared with the construction shown in Figure 4 whereinthe central section I9 is flush with the lower diaphragm surface.

With animproved vent construction as described by the, presentinvention, it is possible to secure escape of excess gas an insureeii'icient and reliable operation of the vent with practical accuracyfor any desired critical pressure in excess oi the` normal operatingvapor pressure in the condenser.

As willbe evident from the above, the invention is not limited tothespeciflc construction shown in the drawing for illustration, but issusceptible of various modifications and variations coming under itsbroad scope as defined in the appended claims.

I claim:

1. A vent for a container subject to internal Aexcess gas pressurecomprising a iiexible diaphragm, a cap lcovering said diaphragm, saiddiaphragm and cap being secured to the edge of an opening of saidcontainer with the outer portion of said diaphragm `i'orming a sealinggasket between said cap and the container, said diaphragm having a thinmid-section with a normally closed puncture therein, and an annularspacer surrounding said mid-section and arranged to project into thespace between said diaphragm and said cap,- the height of said spacerbeing less than the distance between said cap and said diaphragm in itsnormal non-distended condition whereby with increasing gas pressuredeveloped within the container said diaphragm is caused to distend inits entirety towards said cap until checked by said spacer at apredetermined excess pressure, whereupon substantially only saidpunctured section is allowed to distend separately with continuedpressure increase.

2. A vent for a container'subject to internal excess gas pressurecomprising a flexible diaphragm having a central section with a normallyclosed puncture therein, an apertured cap covering said diaphragm,-saiddiaphragm and cap being secured to the edge of an opening of saidcontainer with the outer portion of said diaphragm forming a sealinggasket between said cap and the container, and a concentric annularspacer disposed between said diaphragm and said cap, the height of saidspacer being less than the distance between said cap and said diaphragmin its normal non-distended condition whereby with increasing gaspressure developed within the container said diaphragm is caused todistend in its entirety towards said cap until checked by said spacer ata predetermined eircess pressure, whereupon. substantially only saidpunctured section is allowed to distend separately with continuedpressure increase.

3. A vent for a container subject to internal excess gas pressurecomprising a flexible diau phragm having a central section with anormally closed puncture therein, an apertured cap covering saiddiaphragm, said 'diaphragm and cap being secured to the edge ci? anopening oi said container with the outer portion of said diaphragmforming a sealing gasket between said cap and the container, and anannular concentric spacer integral with said diaphragm and projectinginto the space between said dian phragrn and said cap, said spacer beingnormally spaced from said cap whereby with increasing gas pressuredeveloped within the container said diaphragm is caused to distend inits entirety towards said cap until checked by said spacer at apredetermined excess pressure, whereupon substantially only saidpunctured section is al lowed to distend separately with continued presnsure increase.

d. A' vent for a container subject to internal excess gas pressurecomprising a rubber diaphragm, a cap with a central aperture coveringsaid diaphragm, said diaphragm and cap being secured to the edge of anopening of said conw tainer with the outer portion of said diaphragmforming a sealing gasket between said cap and the container, saiddiaphragm having a thin mid-section with a normally closed puncturetherein, and a concentric annular spacer integral with said diaphragmand projecting into the space between said diaphragm and said cap, saidspacer being, normally spaced from said cap whereby withxincreasing gaspressure developed within the container said diaphragm is caused todistend in its entirety toward said cap until op- .:p'osed by saidspacer ata .predetermined excess pressure, whereupon substantially onlysaid midsection is allowed to distend separately with continued pressureincrease.

5. A vent for a container subject to internal excess gas pressurecomprising a cap having an arched mid-section and an outer rim, a exiblediaphragm having an outer rim and a punctured center section, saiddiaphragm and cap being secured-to an opening of said container with therim of said diaphragm forming a gasket to effect a liquid tight sealbetween said cap and said container, and a concentric annularspacersurrounding said punctured section and projecting into the spacebetween said diaphragm and said cap, the height of said spacer beingless than the distance between said cap and said diaphragm in itsnon-distended condition, whereby with increasing gas pressure developedwithin said container said diaphragm is caused to distend in itsentirety towards said cap until opposed by said spacer at apredetermined excess pressure, whereupon substantially only saidpunctured section is allowed to distend separately with continuedpressure increase.

6. A vent for a container subject to internal excess gas pressurecomprising an apertured cap having an arched mid-section and an 'outerrim, a flexible diaphragm having a thin punctured mid-section and athicker outer rim, said diaphragm and cap being secured to an opening insaid container with the rim of said diaphragm forming a gasket to effecta liquid tight seal between said cap and said container, and an annularspacer surrounding the mid-section of said diaphragm and projecting intothe space between said diaphragm and said cap, the height of said spacerbeing less than the distance between said cap and said diaphragm in itsnon-distended condition whereby with increasing gas pressure developedwithin said container said diaphragm is caused to distend in itsentirety towards said cap until opposed by said spacer at apredetermined excess pressure, whereupon substantially only saidmid-section is allowed to dis tend separately with continued pressureincrease.

7. A vent for a cylindrical container subject to internal excess gaspressure comprising an apertnred cap having an arched mid-section and anouter rim, a rubber diaphragm having a normally flat puncturedmid-section and an outer rire, said diaphragm and cap being secured toan open end of said container with the rim of said diaphragm forming agasket to effect a liquid tight seal between said container and saidcap, and an annular spacer integral with and surrounding saidmid-section of said diaphragm, said spacer projecting into the spacebetween said diaphragm and said cap and being normally spaced from saidcap, whereby with increasing gas pressure developed within saidcontainer said diapznagm is caused to distend in its entirety towardssaid cap until opposed by said spacer at a predetermined excesspressure, whereupon substantially.

only said mid-section is allowed to distend sepa- -rately with continuedpressure increase.

'8. A vent for a container subject to internal excess gas pressurecomprising a cap having an apertured arched mid-section and an outerrim, a rubber diaphragm having a thin center section and an outer rim,said diaphragm and cap being secured to an opening in said containerwith the rim of said diaphragm forming a gasket toeffect a liquid tightseal between said cap and said container, and an annular spacer integralwith and surrounding said mid-section of said diaphagm, said spacerprojecting into the space between said diaphragm and said cap and beingnormally spaced from said cap, whereby with increasing gas pressuredeveloped within said container said diaphragm is caused to distend inits entirety towards said cap until opposed by said spacer, whereuponsubstantially only said punctured section is allowed to distendseparately with con- -separator integral with said diaphragm andsurrounding the mid portion thereof and being normally spaced Yfrom saidcap.

10. A vent structure for a container subject to internal excess gaspressure comprising a ex` ible diaphragm spanning an opening of saidcontainer, an apertured cap spaced from and covering said diaphragm,said diaphragm and said cap being secured to said container, saiddiaphragm having a punctured mid section of lesser thickness than itsouter portion. and an annular sepa yrater integral with said cap andsurrounding said mid section of an normally spaced from said diaphragm.

ll. A vent for electrolytic condensers and the like having a cylindricalcontainer subject to internal excess gas pressure comprising an apeI'-,

tured arched cap secured to an open end of said container, a exiblediaphragm having a thin punctured portion and a thicker edge portion,said edge portion serving as a sealing gasket between the containerand"l said cap, an annular spacer surrounding the punctured portion ofsaid diaphragm, said spacer projecting into the space between saidvdiaphragm and said cap and Ahaving a lesser thickness'than the normaldistance between said diaphragm and said cap, thereby to stop theexpansion of the diaphragm towards said cap at a predetermined excesspressure'A developed within the containerbut to allow said p unc turedportion to expand independently under continued pressure increase beyondsaid prede? termined pressure.

l2. in a vent as claimed in claim 11` whereiny said spacer forms anintegralpart of said diaphragm.

PAUL Mcmerrr DEELEY.

